of Hydrogen and some other Gases. 



345 



column indicates that some volume contraction took place in 

 the tube which was caused by the electric discharge. From 

 the above results we see that the hydrogen obtained by the 

 electrolysis of dilute sulphuric acid contains a small quantity 

 of oxygen diffusing from the anode to the cathode ; that 

 the hydrogen passed through the palladium tube heated 

 above 150° C. does not contain more than 1/150000 volume 

 of oxygen, and by table C, that no air was allowed to enter 

 into the hj-drogen during the process of compressing the gas 

 into the measuring tube. 



§ 10. Concluding Remarks. 



The present experiment is a relative measurement of the 

 susceptibility of gases, in which the susceptibility of pure 

 water is taken as — 0*720 x 10~ 6 . In the measurement of 

 the susceptibility of air, redistilled water was used as the 

 standard substance; for the cases of other gases the air at 

 the ordinary or at some high pressures was used as the 

 substance for comparison. 



The specific susceptibility of gases is assumed to be inde- 

 pendent of pressure, at least in the range of pressure (1 to 

 68 atmospheres) in the present experiment. This assumption 

 was found to be correct within the accuracy of the experi- 

 ment by the fact that the value of the susceptibility of each 

 gas was the same irrespective of the pressure applied, 



The values of the magnetic susceptibilities of the gases 

 investigated in the present experiment are summarised 

 below : — 



Table XIV. 



Gas. 



X.10 6 . K.10 6 . 



Air 4-23'8 5 . -fO0308 4 



Oxygen +104^ +0*148 8 



Carbon dioxide -0-42 3 -0'00083 6 



Nitrogen (chemically pure) -0-26 5 -O'OOO^ 



Nitrogen (atmospheric) — O36 - O00045., 



Argon -5'8 G -0-010 4 



Hydrogen -1-98., -0-000178 l 



In the above fable the specific susceptibilities are referred 

 to the state at 20° C, and the volume susceptibilities to that 

 at 0° C, and 760 ram, pressure respectively. 



